Moving Data Copyright © 2005, Oracle. All rights reserved. Objectives Directory Obj. SQL*Loader Data Pump - Export - Import External Table After completing this lesson, you should be able to do the following: • Describe available ways for moving data • Create and use directory objects • Use SQL*Loader to load data from a non-Oracle database (or user files) • Explain the general architecture of Data Pump • Use Data Pump Export and Import to move data between Oracle databases • Use external tables to move data via platformindependent files 18-2 Copyright © 2005, Oracle. All rights reserved. Moving Data: General Architecture SQL*Loader expdp impdp Other clients Data Pump DBMS_DATAPUMP Data/Metadata Movement Engine Oracle loader Oracle DataPump Direct Path API External Table API 18-3 Copyright © 2005, Oracle. All rights reserved. Metadata API Directory Object: Overview 18-4 Copyright © 2005, Oracle. All rights reserved. . Creating Directory Objects 1 2 3 5 4 18-5 Copyright © 2005, Oracle. All rights reserved. SQL*Loader: Overview Input data files Directory Obj. > SQL*Loader Data Pump - Export - Import External Table Control file SQL*Loader Field processing Accepted Record selection Discarded Rejected Selected Bad file Oracle server Discard file (optional) Inserted Log file 18-6 Copyright © 2005, Oracle. All rights reserved. Rejected Loading Data with SQL*Loader 18-8 Copyright © 2005, Oracle. All rights reserved. SQL*Loader Control File The SQL*Loader control file instructs SQL*Loader about: • Location of the data to be loaded • The data format • Configuration details: – Memory management – Record rejection – Interrupted load handling details • 18-9 Data manipulation details Copyright © 2005, Oracle. All rights reserved. Loading Methods Block writes Data insert Table HWM Conventional Load Direct Path Load Uses COMMIT Uses data saves (faster operation) Always generates redo entries Generates redo only under specific conditions Enforces all constraints Enforces only PRIMARY KEY, UNIQUE, and NOT NULL Fires INSERT triggers Does not fire INSERT triggers Can load into clustered tables Does not load into clusters Allows other users to modify tables during load operation 18-11 Prevents other users from making changes to tables during load operation Copyright © 2005, Oracle. All rights reserved. Data Pump: Overview Directory Obj. SQL*Loader > Data Pump - Export - Import External Table As a server-based facility for high-speed data and metadata movement, data pump: • Is callable via DBMS_DATAPUMP • Provides the following tools: – expdp – impdp – Web-based interface • Provides data access methods: – Direct path – External tables • • 18-13 Detaches from and reattaches to long-running jobs Restarts Data Pump jobs Copyright © 2005, Oracle. All rights reserved. Data Pump: Benefits • • • • • • • 18-14 Fine-grained object and data selection Explicit specification of database version Parallel execution Estimation of the export job space consumption Network mode in a distributed environment Remapping capabilities during import Data sampling and metadata compression Copyright © 2005, Oracle. All rights reserved. Data Pump Export and Import: Overview expdp client Database link Source Target Server process Data Pump job Database Database Dump file set Master table Dump file set Master table “Network mode” Server process Data Pump job impdp client 18-15 Copyright © 2005, Oracle. All rights reserved. Data Pump Utility: Interfaces and Modes • Data Pump Export and Import interfaces: – – – – • Data Pump Export and Import modes: – – – – – 18-16 Command line Parameter file Interactive command line Database Control Full Schema Table Tablespace Transportable tablespace Copyright © 2005, Oracle. All rights reserved. Fine-Grained Object Selection 18-17 Copyright © 2005, Oracle. All rights reserved. Directory Obj. . SQL*Loader Data Pump > - Export - Import External Table Advanced Feature: Sampling • • Task: Create test data. Method: Specify a percentage of data to be sampled and unloaded from the source database. Example to unload 44% of the HR.EMPLOYEES table: SAMPLE="HR"."EMPLOYEES":44 Example to unload 30% of the entire export job (because no table name is specified): expdp hr/hr DIRECTORY=DATA_PUMP_DIR DUMPFILE=sample1.dmp SAMPLE=30 18-18 Copyright © 2005, Oracle. All rights reserved. Export Options: Files 18-19 Copyright © 2005, Oracle. All rights reserved. Data Pump File Locations The order of precedence of file locations: • Per-file directory • The DIRECTORY parameter • The DATA_PUMP_DIR environment variable • DATA_PUMP_DIR directory object 18-20 Copyright © 2005, Oracle. All rights reserved. Scheduling and Running a Job 18-22 Copyright © 2005, Oracle. All rights reserved. Data Pump File Naming and Size 18-23 Copyright © 2005, Oracle. All rights reserved. Data Pump Import 18-24 Copyright © 2005, Oracle. All rights reserved. Directory Obj. SQL*Loader Data Pump - Export > - Import External Table Data Pump Import: Transformations You can remap: • Data files by using REMAP_DATAFILE • Tablespaces by using REMAP_TABLESPACE • Schemas by using REMAP_SCHEMA REMAP_DATAFILE = 'C:\oradata\tbs6.f':'/u1/tbs6.f' 18-25 Copyright © 2005, Oracle. All rights reserved. Data Pump Import: Transformations Using TRANSFORM, you can also : • Exclude from tables and indexes: – STORAGE and TABLESPACE clauses – STORAGE clause only • • Re-create object identifiers of abstract data types Change extent allocations and file size TRANSFORM = SEGMENT_ATTRIBUTES|STORAGE|OID|PCTSPACE:{y|n|v}[:object type] 18-26 Copyright © 2005, Oracle. All rights reserved. Data Pump: Performance Consideration Maximizing job performance with the PARALLEL parameter. Master Coordinator Parallel execution Generated files Example: expdp hr/hr FULL=y DUMPFILE=dp_dir1:full1%U.dmp, dp_dir2:full2%U.dmp FILESIZE=2G PARALLEL=3 LOGFILE=dp_dir1:expfull.log JOB_NAME=expfull 18-27 Copyright © 2005, Oracle. All rights reserved. Performance Initialization Parameters • Performance of Data Pump can be affected by: – DISK_ASYNCH_IO=TRUE – DB_BLOCK_CHECKING=FALSE – DB_BLOCK_CHECKSUM=FALSE • The following should be set high to allow for maximum parallelism: – PROCESSES – SESSIONS – PARALLEL_MAX_SERVERS • The following should be sized generously: – SHARED_POOL_SIZE – UNDO_TABLESPACE 18-28 Copyright © 2005, Oracle. All rights reserved. Data Pump Access Path: Considerations One of the following access paths is automatically selected by Data Pump: • Direct path • External tables, if data includes: – Encrypted columns – Clustered tables – Different partition at unload and load time, and others (see Notes) Database External tables Direct path Database 18-29 Copyright © 2005, Oracle. All rights reserved. Using Enterprise Manager to Monitor Data Pump Jobs 18-30 Copyright © 2005, Oracle. All rights reserved. Directory Obj. SQL*Loader Data Pump - Export - Import > External Table External Table Population . • Unloading of data to external files with the ORACLE_DATAPUMP access driver • No modifications of external tables CREATE TABLE … AS SELECT INSERT … SELECT Unloading Tables 18-31 External files (proprietary format) Copyright © 2005, Oracle. All rights reserved. Loading Tables Using External Tables • • • Data can be used directly from the external file or loaded into another database. Resulting files can be read only with the ORACLE_DATAPUMP access driver. You can combine generated files from different sources for loading purposes. From Oracle Database 18-32 From External File Copyright © 2005, Oracle. All rights reserved. External Table Population with ORACLE_DATAPUMP CREATE TABLE emp_ext (first_name, last_name, department_name) ORGANIZATION EXTERNAL ( TYPE ORACLE_DATAPUMP DEFAULT DIRECTORY ext_dir LOCATION ('emp1.exp','emp2.exp','emp3.exp') ) PARALLEL AS SELECT e.first_name,e.last_name,d.department_name FROM employees e, departments d WHERE e.department_id = d.department_id AND d.department_name in ('Marketing', 'Purchasing'); 18-33 Copyright © 2005, Oracle. All rights reserved. External Table Population with ORACLE_LOADER CREATE TABLE extab_employees (employee_id NUMBER(4), first_name VARCHAR2(20), last_name VARCHAR2(25), hire_date DATE) ORGANIZATION EXTERNAL ( TYPE ORACLE_LOADER DEFAULT DIRECTORY extab_dat_dir ACCESS PARAMETERS ( records delimited by newline badfile extab_bad_dir:'empxt%a_%p.bad' logfile extab_log_dir:'empxt%a_%p.log' fields terminated by ',' missing field values are null ( employee_id, first_name, last_name, hire_date char date_format date mask "dd-mon-yyyy“)) LOCATION ('empxt1.dat', 'empxt2.dat') ) PARALLEL REJECT LIMIT UNLIMITED; 18-34 Copyright © 2005, Oracle. All rights reserved. Data Dictionary View information about external tables in: • [DBA| ALL| USER]_EXTERNAL_TABLES • [DBA| ALL| USER]_EXTERNAL_LOCATIONS • [DBA| ALL| USER]_TABLES, and others 18-35 Copyright © 2005, Oracle. All rights reserved. Summary In this lesson, you should have learned how to: • Describe available ways for moving data • Create and use directory objects • Use SQL*Loader to load data from a non-Oracle database (or user files) • Explain the general architecture of Data Pump • Use Data Pump Export and Import to move data between Oracle databases • Use external tables to move data via platform-independent files 18-36 Copyright © 2005, Oracle. All rights reserved. Practice Overview: Moving Data This practice covers the following topics: • Using the Data Pump Export Wizard to select database objects to be exported • Monitoring a Data Pump Export job • Using the Data Pump Import Wizard to import tables in your database • Using the Load Data Wizard to load data into your database • Loading data by using the command line 18-37 Copyright © 2005, Oracle. All rights reserved.